docs(snowflake): Remove wrong version info for snowflake

[martimors]

This removes the part in the documentation for snowflake where it is claimed 1) we do not support sqlalchemy >=1.4 and 2) snowflake connector version must be pinned to an old version. AFAICT none of these are valid now, so removing.

SUMMARY

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

TESTING INSTRUCTIONS

ADDITIONAL INFORMATION

• Has associated issue:
• Required feature flags:
• Changes UI
• Includes DB Migration (follow approval process in SIP-59)
  • Migration is atomic, supports rollback & is backwards-compatible
  • Confirm DB migration upgrade and downgrade tested
  • Runtime estimates and downtime expectations provided
• Introduces new feature or API
• Removes existing feature or API

[github-actions]

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[mtucker502]

The documentation may have been updated but the official docker image when extended produces the same sqlalchemy 1.4 errors.

Dockerfile:

FROM apache/superset:1.5.3

USER root

RUN pip install snowflake-sqlalchemy

USER superset

Error:

ERROR: pip's dependency resolver does not currently take into account all the packages that are installed. This behaviour is the source of the following dependency conflicts.
apache-superset 1.5.3 requires sqlalchemy!=1.3.21,<1.4,>=1.3.16, but you have sqlalchemy 1.4.46 which is incompatible.
apache-superset 1.5.3 requires typing-extensions<4,>=3.10, but you have typing-extensions 4.5.0 which is incompatible.
Successfully installed asn1crypto-1.5.1 cryptography-38.0.4 filelock-3.9.0 greenlet-2.0.2 oscrypto-1.3.0 pyOpenSSL-22.1.0 pycryptodomex-3.17 snowflake-connector-python-2.9.0 snowflake-sqlalchemy-1.3.1 sqlalchemy-1.4.46 typing-extensions-4.5.0